Gibberellic Acid Use: Considerations and Concerns

Tacy CalliesHLB Management, Tip of the Week

By Tripti Vashisth Gibberellic acid (GA) is a naturally occurring plant hormone. GA has been used in citrus production for years to improve fruit set and size, reduce preharvest drop and delay harvest. Recent findings show that monthly foliar application of GA from September to January can improve productivity of HLB-affected Valencia trees. On average, a 30% increase in yield …

Florida Break-Even Yields and Prices

Tacy CalliesEconomics, Tip of the Week

By Ariel Singerman For processed oranges grown in Southwest Florida during 2020–21, the estimated cultural costs were $1,508 per acre. Total costs of production were $1,882 per acre. Those estimates are down $214 per acre compared to the previous season. This is the result of growers reducing costs across all grove programs, except for fungicides and irrigation. Such a cutback …

Regular Leaf Nutrient Analysis Improves HLB-Affected Trees

Tacy CalliesNutrition

By Tripti Vashisth and Davie Kadyampakeni Nutrition management is complex! Multiple factors affect the nutrient uptake and availability in trees. For example, high soil pH can limit the uptake of soil-applied micronutrients such as zinc (Zn) and manganese (Mn). Oxide forms of nutrients might be less available than nitrate or sulfur forms. Moreover, the time and method of nutrient application …

Lessons on Yield and Root Health From Modified Nutrition

Tacy CalliesNutrition

By Davie Kadyampakeni, Evan Johnson, Kelly Morgan and Ali Atta Citrus production in Florida has been decreasing over the last 15 years due to several factors, with huanglongbing (HLB) a major driver. This disease has severe effects on citrus growth and production, including stunted vegetative growth, misshapen small fruits and poor color development, root mortality, stunted branches, excessive fruit drop, …

Improve Yields With Gibberellic Acid

Ernie NeffHLB Management

Many Florida citrus growers were among the approximately 300 people who registered for a Sept. 21 virtual seminar telling how gibberellic acid (GA) can improve Valencia orange yields. Valencias, at 30.1 million boxes, made up slightly more than half of Florida’s total citrus crop in the 2020-21 season. Presenter Tripti Vashisth started her presentation by saying that GA, already available …

June

All In For Citrus Podcast Has Big HLB News

Tacy CalliesAll In For Citrus Podcast

The September episode of the All In For Citrus podcast is a special edition focused on one subject. University of Florida Institute of Food and Agricultural Sciences (UF/IFAS) researchers have identified a breakthrough treatment for huanglongbing (HLB) that greatly reduces the effects of the disease. Michael Rogers, director of the Citrus Research and Education Center, said a lot of UF/IFAS …

What CRAFT Wants for Cycle III

Ernie NeffCRAFT

Five Citrus Research and Field Trial (CRAFT) Technical Working Group leaders on Aug. 31 discussed the types of projects they’d like to see CRAFT Cycle III growers pursue. The types of projects the leaders expressed interest in will, to some extent, fill gaps in knowledge expected to be gained from previous cycles. CRAFT pays Florida growers to plant trees on …

Technologies for Improved Nutrient Analysis

Tacy CalliesNutrition, Technology

By Yiannis Ampatzidis and Ute Albrecht Nutrient management is important for citrus production. Regular nutrient assessments should be conducted to optimize nutrient balance and prevent deficiencies or over-fertilization. Optimizing nutrition is important for tree health and can improve tolerance to stresses and diseases. Good nutrient management requires regular field monitoring to identify problems and examine crop responses. Leaves need to …

Steps for Reducing Fruit Drop

Ernie NeffFruit Drop

Editor’s Note: Tripti Vashisth with share new information on the use of gibberellic acid treatments to improve health and yield of HLB-diseased trees in a virtual seminar on Sept. 21. Register here. Researcher Tripti Vashisth told the recent Citrus Expo audience how fruit drop might be reduced through the use of nutrition and irrigation strategies, gibberellic acid and increased fruit …

Irrigation Aided by Thermal Imaging

Ernie NeffIrrigation

Scientists in Brazil and Florida found that the direct examination of plant canopy temperature can assist in optimizing citrus irrigation management in greenhouses. The researchers were Gustavo Haddad Souza Vieira with the Federal Institute of Espírito Santo in Brazil and Rhuanito “Johnny” Ferrarezi with the University of Florida Institute of Food and Agricultural Sciences. Their study aimed to develop a …

citrus crop forecast

Navel Oranges: Current Status and Future in Florida

Tacy CalliesVarieties

By Pete Spyke and Bill Castle Navel oranges are fairly tolerant of HLB, are popular and easy to sell, and offer a stable source of income that is only marginally related to worldwide supply and demand. Nevertheless, the Florida navel orange industry has experienced some tough times recently. Growers are questioning whether it is possible to grow navel oranges profitably …

Steger Forecast for 2021-22 Florida Orange Crop

Ernie NeffCrop Forecast

Private consultant Elizabeth Steger on Aug. 16 forecast Florida will produce 52 million boxes of oranges in the 2021-22 season — 1.5% less than the 52.8 million boxes produced in 2020-21. Steger projected 20.8 million boxes of early-midseason oranges; that’s less than the 22.7 million boxes produced last season. Her Valencia projection is 31.2 million boxes; that’s more than the …

orange

Florida Production Faces Further Decline

Ernie NeffForecast, Production

Florida orange and red grapefruit production, already at historically low levels, will likely decline for years, according to a leading citrus economist. Tom Spreen, University of Florida Institute of Food and Agricultural Sciences professor emeritus, calculated Florida crop output through the 2031-32 season based on various yield and tree replacement assumptions. Oranges and red grapefruit are Florida’s top-producing varieties.   …

Citrus History Mystery Solved

Ernie NeffBreeding, Research

How modern citrus developed, particularly the popular mandarin variety, has long been a mystery to citrus breeders. A global partnership of scientists recently unraveled a big part of the mystery by analyzing the genome sequences of 69 East Asian traditional, wild and atypical citrus varieties. One of the researchers was Fred Gmitter, University of Florida Institute of Food and Agricultural …

World Orange and OJ Production to Rise

Ernie NeffCrop Forecast

Worldwide orange and orange juice (OJ) production are projected to climb in the 2020-21 market year, the U.S. Department of Agriculture’s Foreign Agricultural Service (FAS) reported recently. ORANGESGlobal orange output for 2020-21 is estimated up 2.5 million tons from the previous year to 48.6 million as favorable weather leads to a larger crop in Brazil (up 7%) and Mexico (up …

Improved Orange Cultivars

Ernie NeffVarieties

Improved sweet orange cultivars for processing and fresh fruit were the topic of a virtual presentation July 14 by plant breeder Jude Grosser. Grosser works at the University of Florida Institute of Food and Agricultural Sciences Citrus Research and Education Center in Lake Alfred.   HAMLIN SOMACLONE N13-32This new and distinct early-season clone of Hamlin has improved juice color and …

Mandarin Production Rises Sharply in EU

Ernie NeffInternational

Mandarin production in the European Union (EU) in 2020-21 is forecast to rise 21% from the previous year, to 3.4 million metric tons. The forecast, reported by the U.S. Department of Agriculture’s Foreign Agricultural Service, is almost 10% higher than the union’s 9-year average of 3.1 million metric tons. The higher production this season is mainly the result of expected …

alico

CRAFT May Encourage Early-Mid Orange Plantings

Ernie Neffplanting

Officials with the Citrus Research and Field Trial (CRAFT) program are considering giving future participating growers an incentive to plant more early- and mid-season oranges. The topic was discussed by CRAFT’s board of directors after board member Phillip Rucks pointed out there’s a trend for nurseries to propagate far more late-season oranges than early- and mid-season oranges. Tables that the …

What To Do About Algal Spot

Tacy CalliesDiseases, Tip of the Week

By Megan Dewdney I did not need to visit my field trial to know that algal spot was in bloom on citrus in the last month. I have received many phone calls about it recently as growers notice the bright orange doughnuts on their tree limbs. For those unfamiliar with algal spot, it is a disease that occurs mostly on …

florida

Final U.S. Citrus Crop Forecast Sees Changes

Daniel CooperCrop Forecast

The U.S. Department of Agriculture’s (USDA) final 2020-2021 Florida orange forecast is 52.8 million boxes. California orange production edged out Florida with 54.5 million boxes of oranges. Texas oranges remained at 1.05 million boxes. The final Florida orange total is comprised of 22.7 million boxes of non-Valencia oranges (early, midseason and Navel varieties), unchanged from the June forecast, and 30.1 …